805021440 has 144 divisors (see below), whose sum is σ = 2660061600. Its totient is φ = 207241216.

The previous prime is 805021421. The next prime is 805021457. The reversal of 805021440 is 44120508.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 805021440.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 107746 + ... + 114974.

It is an arithmetic number, because the mean of its divisors is an integer number (18472650).

Almost surely, 2^805021440 is an apocalyptic number.

805021440 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 805021440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1330030800).

805021440 is an abundant number, since it is smaller than the sum of its proper divisors (1855040160).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

805021440 is a wasteful number, since it uses less digits than its factorization.

805021440 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7282 (or 7268 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 24.

The square root of 805021440 is about 28372.8997460605. The cubic root of 805021440 is about 930.2560053687.

Adding to 805021440 its reverse (44120508), we get a palindrome (849141948).

The spelling of 805021440 in words is "eight hundred five million, twenty-one thousand, four hundred forty".